The need to improve effectiveness
The overall information that we collect from these experiences notifies
us that LPW plays a pivotal role in the maintenance of AF and it should
be included in the ablative approach of patients with persistent AF.
Probably in order to obtain an effective and durable LPWI the scheme of
lesions should be properly revisited as to reduce the likelihood of
electrical reconnection of the posterior wall. My own perplexity is
about the ablative modality of creating linear lesions reported in this
and other studies, since the rate of inconsistency of the lesions
connecting the contralateral PVs is well documented. In this regards,
the promotion of LPW homogenization by moving a circular catheter around
the PV antrum can significantly reduce the arrhythmia recurrence rate as
compared to the circle of contiguous lesions (12). Unfortunately, even
in the study by Sayuri et al the rate of LPW reconnection is high,
underlying the technical difficulty to achieve a durable effectiveness.
The good news from the study is revealed by the lower occurrence of
atrial tachycardia (AT, 9%) in patients who underwent PVI plus LPWI and
this is much lower than in previous studies, where the rate of recurrent
AT varied from 5% to 59%. (see 21-23 Sayuri). On the other hand, due
to the disparity of approaches employed in the different studies, it is
difficult a fair and objective comparison. Due to the observational
nature of this single center study and the limited number of patients
included, caution needs to be advocated concerning the value of creation
linear lesions with the current technology. The emerging ablative
techniques, such as high power-short duration ( see 27 Sayuri) and the
use of ablation index (see 28 Sayuri) or the promising
thermal/non-thermal pulse field ablation technology might constitute the
technical key improvement to provide an effective LPWI. Future studies
are needed to evaluate whether these additional approaches improve
clinical outcomes, provided isolation of LPW is guaranteed
Even with the inherent limitations of the study, we need to applaud
Sayuri er al for drawing our attention to the pivotal role of left
posterior wall in the initiation and maintenance of AF and, thus
reinforcing the concept of walking out of the PVs towards the posterior
wall. Achieving proven isolation of LPW is essential to promote
additional benefits over PVI alone in the treatment of persistent AF and
the adoption of new ablation settings and novel energy delivering is
required to improve procedural outcome over the follow-up